I have to upload on an ftp virtualbox server 24h/24h images file from camera DVR. Actually I have continuously connected 5 user, up to 30 session each, 1milion file uploaded day. The use of memory is under 20%, the load under 2, the network up under 10Mb/s, everything fine. The big problem is a CRASH every some hours for memory problem I suppose. Initially I thought was a bug on debian / proftpd. So I tried using ubuntu server / vsftpd, and after centos / pure ftpd (I tried the vm from tutorial in this site). The same problems. Now I know that is a memory use problem. With vsftpd I have a cache and buffer memory grow up, with pureftpd seem only a cache memory grow up. I tried to clean with cron the memory with echo 1 > /proc/sys/vm/drop_caches, but I don-t solved. If I use echo 3 > /proc/sys/vm/drop_caches seems all go well for a longer time but sometimes I have a crash. I need to tune quickly my server for production and after weeks of tests I'm disperated. Some help? If there is an expert that can help me....
Did you consider (as a temporary workaround) to use monit to monitor the process (used memory) and restart the service when it exceeds a given level?
Thank you for your idea, but if I restart the service I will lost some upload images. I need all time server up. But I'm asking a question? It is normal my memory problem in my situation? How do the company that have production server bigger than mine to solve the problem if they have? Some people told me is not ok a virtual ftp machine, but all the world today work with VM. So, I have a standard situation or not? Thank you for your help
Actually the problem is on your VM image howtoforge_pure-ftpd-virtual-ftp-server-centos-7-2. I hoped that with an image not from mine I solve the problem. Now I have support to discover the kernel problem that I have. On that image I made only update and upgrade and installed Vbox guest additions and little utilities. I will tell you the conclusion when I will find.
